A conventional mascara brushes has a straight core member and many brush bristles being fixed to the core member and extending radially. When the many bristles are not subjected to special processing, they have shapes extending radially from the core member in an orderly manner. On the other hand, since liquid retainability of a mascara liquid is determined by wettability of surfaces of brush bristles and the surface tension of the mascara liquid itself, the mascara liquid may flow fluently but the liquid retainability may be poor even only when the brush bristles are just arranged in the orderly manner. If the liquid retainability is poor, there is a possibility in which a large amount of the mascara liquid retained in the mascara brush transfers to eyelashes at a time, and solidly filling may occur or a liquid drop lump may be produced and so on, and thus, satisfactory finishing may be hardly accomplished. In addition, if the liquid retainability is poor, it is required to add the liquid at frequent intervals, causing makeup with the mascara to be difficult.
On the other hand, when the brush bristles is processed through only taking the liquid retainability into consideration, the eyelashes are hardly allowed to sufficiently enter the inside of the brush, an amount of the mascara liquid applied to the eyelashes is decreased, and thus, so-called catch-up feel of wrapping and holding eyelashes and so-called volume-up effect of voluming eyelashes up may not be sufficiently provided. Accordingly, a mascara brush is required to satisfy both of sufficient catch-up feel and sufficient volume-up effect.
For obtaining both of them, PTL 1 proposes mixing two kinds of brush bristles having melting temperatures different from each other, melting tips of the brush bristles having the low melting temperature to make brush bristles having short lengths and forming lumps whose diameters larger than those of the brush bristles at the tips of the brush bristles. If this is accomplished well, it may be possible to satisfy both of sufficient catch-up feel and sufficient volume-up effect.
In addition, PTL 2 proposes heating and bending the brush bristles at the plural areas in circumferential directions around the core member to ensure the liquid retainability by the brush bristles, thereby obtaining the catch-up feel and the like at boundary areas between the bent brush bristles and brush bristles extending long without being bent.